(The following excerpt from a chapter Aaron Beck and I wrote for Clarkin & Lenzenweger ‘s (1996) book Major Theories of Personality Disorder gives a pretty good summary of CT’s current views on development.. While it focuses specifically on the developmental origins of personality disorders the same points apply to CT’s views of development in general.)

Inherited Predispositions

A number of heritable characteristics are relevant to understanding the development of personality disorders. First, it can be argued that, over the course of evolution, natural selection molded durable predispositions into humans which served the basic evolutionary goals of survival and reproduction. As our social milieu has changed from small groups subsisting in the wild to an advanced technological society, evolution may well have not kept pace with social change and thus there may well be areas of "poor fit" between our inherited predispositions and the demands of modern society which tend to cause problems for humans in general. If individuals differ in the strength or nature of these inherited predispositions, this could predispose certain individuals towards the development of particular problems. Beck (1992) has hypothesized that inherited predispositions towards certain "primeval strategies" (below) may contribute to the development of certain personality traits.

Several cognitive-behavioral authors have hypothesized that inborn defects or deficits play an important role in the development of personality disorders. For example, Linehan (1987a, b, c) has hypothesized that individuals with borderline personality disorder have an inherent defect in the regulation of emotion. She argues that this inborn defect interacts with a learning history which did not support the adaptive expression of emotion to result in intense, poorly-controlled emotional responses. Similarly, Turner (1986) argues that borderlines have a biological predisposition towards low stress tolerance which interacts with maladaptive schemas to distort information processing. However, recent Cognitive conceptualizations of Borderline Personality Disorder (Beck, et al., 1990, Chapt. 9; Freeman, et al., 1990, Chapt. 8; Pretzer, 1983) have argued that these phenomena can be understood in terms of the effects of dysfunctional beliefs, cognitive distortions, and learning history without any need to postulate any inborn differences between individuals who develop Borderline Personality Disorder and those who do not. Certainly, if inborn defects in information processing, regulation of affect, or in interpersonal behavior occur with sufficient frequency, this would be relevant for understanding the development of personality disorders. However, it is not yet clear if such defects actually play a significant role in the development of personality disorders or not.A potentially heritable aspect of individual development relevant to understanding the development of personality disorders is the infant's temperament. If one infant inherits a tendency to be extroverted and confident while another inherits a tendency to be shy and retiring, we would expect the shy, retiring infant to be more likely to eventually develop avoidant personality disorder. However, the development of schemas and of interpersonal strategies are both strongly influenced by life experience. An inherently shy and retiring child who experiences day to day life as calm and secure might gradually risk being a bit more adventuresome. If his or her initial attempts at being somewhat bolder seem to work out well, he or she might conclude that risk-taking is a good idea and gradually become less shy and retiring or might develop adaptive ways of coping with his or her shyness. However, a child who experiences daily life as frightening might avoid risk-taking as much as possible and therefore not have the experiences which would lead him or her to conclude that risk-taking is a good idea. Similarly, a child who experiments with being a bit more adventuresome and perceives his or her boldness to have bad consequences is not likely to persist with risk-taking. Either of these children might well persist in being shy and retiring, fall behind his or her peers in developing social skills, and become more and more socially isolated. However, the role of these possible inherited predispositions towards certain personality disorders is not a simple, straightforward one. First, the interaction between the child's predispositions, his or her family environment, and significant life events would shape development rather than inherited predispositions alone shaping development. Second, it is important to note that it is not objective events but the child's perception of events which influences the development of schemas and interpersonal strategies. Since cognitive development occurs in a series of stages over the course of childhood and adolescence, children are at a substantial disadvantage in attempting to understand the complexities of daily life. Misunderstandings and misinterpretations can easily occur because of the child's limited life-experience and limitations imposed by the stage of cognitive development which he or she has attained.

Learned Characteristics

The many processes involved in social learning are also likely to play major roles in the development of personality disorders. Parents and significant others influence the developing child through verbal communication and explicit teaching, through their modeling of behaviors, through the contingencies they impose on the child, and through the cultural influences they transmit. A shy, retiring child might be explicitly or implicitly taught by his or her parents that one should avoid uncomfortable situations or might be taught that one should face one's fears. This would have obvious influences on the child's development. However, the parents might well give conflicting messages because the two parents disagree with each other, because one or both of the parents is ambivalent about the wisdom of facing one's fears, or because the parents' words are not consistent with their actions. As the child implicitly experiments with ways of understanding and responding to a particular type of recurrent situation and finds an approach which seems to work, the child may well "specialize" in a particular approach because it is strongly reinforced by the responses of others, because the situation seems risky enough to discourage further experimentation, or simply because it is the best approach the child has been able to discover.

The Developmental Impact of Traumatic Experiences

The long-term effects of traumatic events have been emphasized in many traditional perspectives on personality development. According to Cognitive theory, the underlying assumptions and interpersonal strategies which are emphasized in the Cognitive model of personality disorders are based on the individual's previous experience and this certainly would include any traumatic events which have occurred. The extreme experiences which some children encounter (see Bowlby, 1985, for striking examples) certainly can have important and lasting impacts on an individual's development. It may be possible for a single, dramatic experience to have lasting effects, but we would expect experiences which are recurrent, which are part of a consistent pattern of events, or which strengthen existing preconceptions to be particularly likely to have lasting effects. An individual's early experiences play an important role in the development of personality disorders and other psychopathology for several reasons. After all, childhood experiences occur during the period where initial schemas are being established, the child is exposed to the family environment daily over a period of years, parents are emotionally important to the growing child, and parents have control over powerful reinforcers and punishers. Childhood experiences are particularly important because once a child's initial schemas and interpersonal strategies are established, they shape the perception and interpretation of subsequent experiences in a way which tends to produce a "confirmatory bias" or "feed-forward mechanism" (Mahoney, 1974, 1977). Individuals tend to selectively attend to experiences which are consistent with their preconceptions and to be biased towards interpreting their experiences as confirming these preconceptions in such a way that once schemas are established, they tend to function as self-fulfilling prophecies. Therefore these cognitive structures tend to persist once they are established.To return to our case example, Gary believed that people in general were malicious and deceptive, that they would attack him if they got a chance, and that the way to be safe was to be vigilant, on guard, and ready to defend himself. How did he come to hold these views? According to Gary's descriptions, he grew up in a family where a suspicious, vigilant approach to the outside world was explicitly taught by his parents both through their words and their example. In addition, family members had been physically and verbally abusive of him and each other throughout his childhood, and had frequently taken advantage of him from childhood through the present. In short, he reported growing up in a family environment where his world-view and interpersonal strategies were explicitly taught and were strongly reinforced by repeated experiences. Of course, we cannot be certain regarding the accuracy of Gary's perception and recall of interactions in his family of origin. However, it was his subjective experience rather than objective reality which, over time, gave rise to generalized beliefs about his world and his role in it. To a certain extent, the objective reality is unimportant since it is the individual's interpretation of experience which gives rise to both immediate responses and more persistent memories, beliefs, and assumptions.The question of the extent to which there are inherent differences between individuals with personality disorders and individuals who do not have personality disorders is likely to remain a matter of theoretical debate until there are long-term longitudinal studies which examine the extent to which differences observed in infancy predict the subsequent development of personality disorders. When differences between individuals with a given personality disorder and "normal" individuals are identified in cross sectional research, it can be difficult to determine to what extent an observed difference between groups is an inherent difference which contributed to the development of the disorder, to what extent the difference reflects characteristics which were acquired in the course of development, and to what extent the difference is a product of the individual's disorder. However, this question is of limited relevance for clinical practice. It is much more important clinically to identify methods for accomplishing therapeutic changes than to identify inherent differences.